1. Field of the Invention
High voltage cable is provided with a shield conductor outside of the cable itself to provide a return circuit for load currents and also to maintain the outside surface of the cable at ground potential. This shield conductor often takes the form of a number of wire braids wrapped about the cable jacket and is termed a concentric neutral. This concentric neutral being outside of the normal cable jacket is not protected from the environment in which it is buried and is subject to the corrosive effects of water, acids, bases and other chemical substances now regularly found almost everywhere. The destruction of this concentric neutral removes the return path for the load currents and could cause increasing voltage potentials of the shield and could render any contact with the energized cable dangerous.
The industry has countered the injury to the concentric neutral by placing a jacket over the entire cable concentric neutral and all. High voltage cable being heavy and large in size can only be fabricated in relatively short lengths. These lengths must be spliced and the joints protected so that the cable is protected as well as the fittings.
The invention herein is directed to a housing which can be placed over a high voltage cable splice and sealed to prevent the entrance of environmental materials into the splice which could attack such splice and the associated cables.
2. Description of the Prior Art
U.S. Pat. No. 2,978,533 issued Dec. 26, 1957 shows a cable splice enclosure made of two rubber portions made to overlap and locked to one another by means of an external hose clamp. Likewise the end seals are accomplished by hose clamps giving a limited adjustment range. Exposed metallic hose clamps would have a short useful life buried in the ground and could provide electrical hazards.
U.S. Pat. No. 3,705,950 issued Dec. 12, 1972 makes use of a central container screw threaded at both ends. Two conical end portions, one for each end, are screwed onto the central container and have stepped ends to match various diameter cables. Closure is also achieved by means of external, metal hose clamps.
The cable connector box shown is U.S. Pat. No. 3,818,124 issued June 18, 1979 makes use of a central plastic cylinder with plastic end caps. The ends of the caps are stepped to accommodate different diameter cables. It is assumed that the resiliency of the end caps causes it to conform to the central cylinder diameter and the various cable diameters and give tight seals at the interfaces. Such an arrangement is limited in the number of steps which the end caps contain and require that the caps be forced along the cable during installation making their use more difficult.
U.S. Pat. No. 3,274,330 issued Sept. 20, 1966 uses a crimpable connector with a depressed central section upon which is placed an insulating sleeve rolled from both ends. Once the two cables are crimped, the sleeve is unrolled. This arrangement is only usable as a part of the splice device itself and not as an insulator and protector of a separate and distinct splice member.
In U.S. Pat. No. 3,824,331 issued July 16, 1974 an insulation sleeve is provided for a splice and the exposed cable ends adjacent thereto. The sleeve is rolled from both ends towards the center over a tube holding the sleeve expanded and the ends are positioned in a retainer. After positioning over the crimped splice the expander tube is removed to allow the sleeve to return to its desired size. The tube is unrolled from both ends and the retainer is broken off.